Grape Plant Named &#39;A-2640&#39;

ABSTRACT

A grape cultivar particularly distinguished by large, seedless, black-skinned berries, large clusters, with a mid to late season of ripening, high productivity and good vine health, is disclosed.

GENUS AND SPECIES

Vitis hybrid (Vitis labrusca L.×Vitis vinifera L.)

VARIETY DENOMINATION

‘A-2640’

BACKGROUND OF THE NEW PLANT

The present invention comprises a new and distinct cultivar of Vitis, botanically known as Vitis hybrid (Vitis labrusca L.×Vitis vinifera L.), and hereinafter referred to by the cultivar name ‘A-2640’. ‘A-2640’ originated from a hand-pollinated cross of the female Vitis labrusca L.×Vitis vinifera L. ‘Arkansas Selection 1925’ (unpatented) with the male Vitis labrusca L.×Vitis vinifera L. ‘Arkansas Selection 2020’ (unpatented) made in 1992 near Clarksville, Ark. (west-central Arkansas).

The seeds resulting from the controlled hybridization were germinated in a greenhouse during the winter of 1992-1993 and the resulting seedlings were planted in the spring of 1993 in a vineyard at Clarksville, Ark. The seedlings fruited in the summer of 1996 and a single selection designated ‘Arkansas Selection 2640’ was selected for its large seedless, oblong fruits with no seed traces, neutral flavor, large clusters, and overall very good fruit quality.

During 1996, ‘Arkansas Selection 2640’ was propagated asexually in Clarksville, Ark. by rooting hardwood cuttings. A test planting of three vines was established and the instant plant was subsequently named ‘A-2640’. Subsequently, larger test plantings were established with asexually multiplied vines in Clarksville, Ark. and near Delano, Calif. (Kern County). In all propagations, hardwood cuttings were used. ‘A-2640’ roots readily from hardwood cuttings. All propagules (resulting plants) of ‘A-2640’ have been observed to be true to type through successive asexual propagations and the vegetative and fruit characteristics of the original plant have been maintained. All vines planted from hardwood cutting propagation fruited in the second or third season of growth in the vineyard after planting.

Test plantings at the above two locations have shown ‘A-2640’ to be most adapted to the Delano, Calif. test site, where the vines produce consistently high yields of fruit with large berries and clusters along with no fruit cracking at maturity. In Arkansas, ‘A-2640’ has excellent fruit quality and no seed traces, but a substantial limitation observed is fruit cracking following rainfall when fruits are ripe.

The new cultivar was discovered in Clarksville, Ark. and has been asexually reproduced repeatedly by rooting hardwood cuttings over a 12-year period. The present invention has been found to retain its distinctive characteristics through successive asexual propagations.

SUMMARY OF THE INVENTION

The following are the most outstanding and distinguishing characteristics of the new cultivar when grown under normal horticultural practices in west-central Arkansas and Delano, Calif.

-   -   1. Vines having medium to high vigor, with an upright growth         habit characteristic of Vitis vinifera;     -   2. Produces well-rooted plants;     -   3. The fruit ripens in the mid-to-late season, with the average         first harvest date being August 20 in west-central Arkansas and         Delano, Calif.;     -   4. The fruit quality is maintained well on the vine after         maturity and the fruit quality for marketing is maintained for         up to two to three weeks on the vines after initial maturity is         reached;     -   5. Berries that adhere well to the fruit pedicel and do not         shatter from the clusters during growth or harvest;     -   6. Black-skinned berries at early maturity. The fruit is evenly         colored within the cluster and the berries are oblong-shaped;     -   7. Fruit skins that are medium-thick and adhere to the flesh;     -   8. Berries that are medium-large in size (about 4.5 g) and a         flesh flavor that is neutral and sweet with soluble solids         concentration of the juice at fruit maturity averaging 18% with         low to medium acidity;     -   9. Fruit that is of the stenospermocarpic type of seedlessness         and contains small, soft vestigial seed traces that are not         noticeable when eaten; and     -   10. Fruit clusters that are borne usually two per shoot, are         large, well-filled, but not overly tight. Fruit cluster         peduncles are medium-long and easy to remove from the supporting         shoots during harvest.

DESCRIPTION OF THE PHOTOGRAPHS

This new Vitis hybrid plant is illustrated by the accompanying photographs which show a representative bunch of grapes, foliage and segments of vines; the colors shown are as true as can be reasonably obtained by conventional photographic procedures.

FIG. 1 shows a representative bunch of grapes, foliage and segments of vines.

FIG. 2 shows a close-up of a mature leaf.

DESCRIPTION OF THE NEW CULTIVAR

The following detailed descriptions set forth the distinctive characteristics of ‘A-2640’. Where dimensions, sizes, and other characteristics are given, it is to be understood that such characteristics are approximations of averages set forth as accurately as practicable. The colors are as nearly true as is reasonably possible in a color representation of this type. The plant history and descriptions are taken from specimens grown at Delano, Calif. unless otherwise indicated. Vines used for measurement were irrigated using trickle (drip) irrigation. The majority of the data collection was from vines that were 5-years-old unless otherwise indicated. The color readings were determined under natural light. Color references are to the R.H.S. Colour Chart of The Royal Horticultural Society of London (R.H.S.) (2001).

DESCRIPTION OF THE NEW PLANT

-   Classification:     -   -   Family.—Vitaceae.         -   Botanical name.—Vitis hybrid (Vitis labrusca L.×Vitis             vinifera L.).         -   Common name.—Grapevine.         -   Denomination.—‘A-2640’. -   Parentage:     -   -   Female parent.—The Vitis labrusca L.×Vitis vinifera L.             ‘Arkansas Selection 1925’ (unpatented).         -   Male parent.—The Vitis labrusca L.×Vitis vinifera L.             ‘Arkansas Selection 2020’ (unpatented). -   Vine:     -   -   Size.—Medium.         -   Growth.—Moderately vigorous to vigorous.         -   Density of foliage.—Medium.         -   Productivity.—Very productive.         -   Rootstock.—Vines are grown and tested on their own-rooted             vines.         -   Cold hardiness.—Hardy to −15° C.         -   Trunk.—Shape: Slender Straps: Long, split Surface texture:             Shaggy Inner bark color: RHS 177B (Greyed-Orange) Diameter:             20.67 cm for eight year old vines at a height of 1.0 m above             the ground.         -   Shoots (current-season canes).—Shoot tips: Slightly open;             RHS 145A (Yellow-Green) shoot tips have very weak RHS 61A             (Red-Purple) anthocyanin present in the shoots and the             distribution of anthocyanin is absent at the tip Density of             prostrate hairs: Very dense Density of erect hairs: Absent             Shape: Rounded Length: 157.6 cm at 2.5 months after budbreak             Diameter: 1.2 cm at 2.5 months after budbreak in the middle             of the first two nodes from the attachment point Vigor             during flowering: Very strong Attitude during flowering on             shoots which are not tied: Horizontal Color of dorsal and             ventral sides of internodes: RHS 144A (Yellow-Green) Color             of dorsal and ventral sides of nodes: RHS 144A             (Yellow-Green) Density of erect hairs on nodes and             internodes: Absent Density of prostrate hairs on nodes: Very             sparse Anthocyanin coloration of buds: Absent.         -   Tendrils.—General: Trifurcated with medium thickness and a             discontinuous distribution at full flowering Length             (measured at full flowering): Very long, 30 cm Color (at             full flowering): RHS 145A (Yellow-Green) Number of             consecutive tendrils: Up to two Pattern: Flowering node             4^(th) to 5^(th), then followed by tendrils on 6^(th),             8^(th), 9^(th), 11^(th), 12^(th), 14^(th), 15^(th) nodes. -   Buds:     -   -   General.—Basal buds are most fruitful and seldom dead.         -   Time of budbreak.—Medium; about March 3.         -   Shape.—Pointed. -   Canes (mature canes):     -   -   Length.—249.8 cm.         -   Shape.—Stocky.         -   Surface texture.—Striate.         -   Internode length.—Long, 14.0 cm.         -   Width at node.—1.28 cm.         -   Cross section.—Circular.         -   Color.—RHS 166D (Greyed-Orange).         -   Density of erect hairs of nodes and internodes.—None or very             sparse.         -   Growth of axillary shoots from the mature cane.—57.4 cm.         -   Lenticels.—Quantity: 47 per 0.5 cm² Shape: Round but             occasionally oblong Length: 0.12 cm Width: 0.03 cm Color:             RHS 202 A (Black). -   Leaves:     -   -   Immature (unfolded, 4^(th) distal).—Color: RHS 146A             (Yellow-Green) Pubescence density: Prostrate hairs between             veins: Very dense Erect hairs between veins: Very sparse             Prostrate hairs on veins: Dense Erect hairs on veins: Medium             Anthocyanin coloration of six distal leaves prior to             flowering: Weak, RHS 61A (Red-purple) but appears coppery             from being diffused with the yellow-green background color             of the leaves.         -   Mature.—Type: Simple, alternate Shape: Pentagonal Profile:             Involute Apex: Occurs in the plane of the leaf; obtuse Base:             Cordate Margin: Serrated Quantity of lobes: 3 to 5             Serration: Entire Tooth length: 0.93 cm on the middle tooth             of the basal lobe Tooth width: 1.54 cm on the middle tooth             of the basal lobe Tooth shape: Incised Quantity of teeth per             lobe: About 10.2 Number of teeth per leaf: About 51 Size:             Very large; height is 11.3 cm, length is 18.0 cm and width             is 23.6 cm Thickness: Medium Shape of petiole sinus:             Slightly open Tooth at petiole sinus: Absent Petiole sinus             limited by veins: Absent Shape of upper lateral sinus: Open             Depth of upper lateral sinus: Shallow Margin undulation:             Pronounced undulation with overall undulation between the             main and lateral veins; small ratio length/width Upper             surface: Color: RHS 146A (Yellow-Green) Surface texture:             Rugose, dull in appearance; pubescence present on veins             Lower surface: Color: RHS 146B (Yellow-Green) Surface             texture: Rugose, dull in appearance, glossiness is weak             Anthocyanin vein coloration: Absent Pubescence density:             Prostrate hairs between veins: Medium Erect hairs between             veins: Very sparse Prostrate hairs on main veins: Medium             Erect hairs on veins: Medium.         -   Petiole.—Length: Very long (23.9 cm), much longer when             compared to middle vein Diameter: 0.33 cm Pubescence:             Density of prostrate hairs: Sparse Density of erect hairs:             Sparse; sinus Shape of base of petiole sinus: V-shaped             Color: RHS 144B (Yellow-Green). -   Flowers:     -   -   Sex/type.—Hermaphrodite, borne in a cluster of flowers             (inflorescence).         -   Quantity of flowers per cluster.—486.2.         -   Quantity of flower clusters per vine (plant).—About 35.2.         -   Quantity of individual flowers per vine (plant).—About             17,114.24.         -   Fragrance.—Absent.         -   Flower depth.—0.3 cm.         -   Flower width.—0.19 cm.         -   Inflorescence length.—Very long, 32.1 cm.         -   Quantity of inflorescences.—2 to 3 per shoot.         -   Date of bloom.—Mid-season; first bloom is about May 7 and             full bloom is about mid-May.         -   Petals.—Quantity per flower and appearance: 5, petals are             fused into a cap, or calyptra, which dehisce from the base             at the time of bloom Length: 0.23 cm Width: 0.11 cm Apex:             Acute Base: Truncate Margin: Entire Color, upper surface:             RHS 144A (Yellow-green) Color, lower surface: RHS 144A             (Yellow-green).         -   Sepals.—Absent. -   Reproductive organs:     -   -   Stamens.—Aspect: Erect Quantity per flower: 5 or 6 Anther:             Length: 0.13 cm Width: 0.1 cm Color: RHS 143A (Yellow-green)             Pollen: Quantity: Abundant Color: RHS 13C (Yellow).         -   Pistil.—Size, general: Medium-long Quantity per flower: 1             Stigma: Quantity: 1 Length: 0.036 cm Width: 0.072 cm Color:             RHS 154D (Yellow-green) Style: Quantity: 1 Length: 0.038 cm             Width: 0.060 cm Color: RHS 143A (Green) Ovary: Quantity: 1             Length: 0.096 cm Diameter: 0.124 cm Color: RHS 143A (Green). -   Fruit:     -   -   Maturity.—Medium-late; 20 days after ‘Thompson’             (unpatented); first harvest date is approximately August 20.         -   Berry.—Seed presences: Seedless, rudimentary seed traces are             present but very small Size/Weight: Medium-large, 4.5 g per             berry and uniform in size Shape: Oblong; cross section             circular; length 2.40 cm; width 1.74 cm Color (skin): RHS             202A (Black) Flesh: Non-slipskin, crisp; medium-firm; juicy;             very slight anthocyanin color in flesh where flesh contacts             the skin (to the depth of the skin); the flesh has a very             slight RHS 83A (Violet) that extends to about 1/10 of a             millimeter into the flesh while the rest of the flesh does             not have a distinct color but is overall translucent Brush             length: Medium Soluble solids: 18% Acidity: Low to medium;             0.46 g/100 mL expressed as tartaric acid Flavor: Neutral and             sweet Skin: Thickness is medium; texture is medium;             reticulation absent; roughness absent; tenacious to flesh;             bloom is medium; ground and blush colors are absent Pedicel             length: Intermediate; berry separation from pedicel medium;             the diameter is 0.042 cm and the length is 0.142 cm Hilum             visibility: Unclear Eating quality: Very good with good             crispness and a mostly neutral flavor and sweet Shipping             quality: Good, with good berry retention to the pedicel             Tendency to crack: There is little tendency to crack unless             rainfall occurs at full-maturity which can lead to some             cracking or splitting of the skin.         -   Cluster.—Mature cluster weight: Very large; 1.135 g Mature             cluster length: Very long; 38.0 cm Mature cluster width:             Medium; 21 cm Quantity of berries per cluster: 277 Density:             Medium loose Form: Conical Peduncle: Length: Very long; 7.1             cm Lignification: Medium Color: RHS 144A (Yellow-Green). -   Disease and insect resistance: The new cultivar is moderately     resistant to powdery mildew (Uncinula necator Burr.) but is     susceptible to downy mildew (Plasmopora viticola Berl. & Tomi.),     black rot (Guignardia bidwellii (Ell.) V. & R.), and anthracnose     (Elsinoe ampelina (d. By.) Sher). Fungal diseases can be controlled     by the use of available fungicides. -   Use: For fresh-market use

COMPARISON WITH PARENTAL AND COMMERCIAL CULTIVARS

‘A-2640’ differs from the female parent, the female Vitis labrusca L.×Vitis vinifera L. ‘Arkansas Selection 1925’ (unpatented) in that ‘A-2640’ is a seedless grape, while ‘Arkansas Selection 1925’ is a seeded grape. Additionally, ‘Arkansas Selection 1925’ ripens approximately one week before ‘A-2640’.

‘A-2640’ differs from the male parent, the Vitis labrusca L.×Vitis vinifera L. ‘Arkansas Selection 2020’ (unpatented) in that ‘A-2640’ has oblong-shaped berries, while ‘Arkansas Selection 2020’ has semi-oval-shaped fruit. Additionally, ‘Arkansas Selection 2020’ has a lighter flesh color than ‘A-2640’.

‘A-2640’ differs from the commercial cultivar ‘Jupiter’ (U.S. Plant Pat. No. 13,309) in that ‘A-2640’ is less hardy in cold winters than ‘Jupiter’. 

1. A new and distinct cultivar of grape plant as shown and described herein. 